Hey there @Juice71288 - thanks for your post!

For some context, with Calendly, there are two types of invitee booking notifications: Email Confirmations & Calendar invitations.

1. With Email Confirmations, Calendly sends the invitee an email notification from notifications@calendly.com and has a reply-to address that's associated with your Calendly login email. You can modify this on Account Settings page.
2. With Calendar Invitations, your connected calendar sends the invitee a notification of the booked meeting which has a reply-to address that's associated with your Add to calendar email on your Calendar Connection page.

Note: Calendar invitations are not compatible with iCloud Calendar or the Outlook Plugin (for Windows users). Users with either of these calendar connections set up as their "add-to calendar" on their Calendar Connection page will be defaulted to Email Confirmations. 

So, if calendar invitations are not available to you, it’s likely because you are trying to set them up for a Group event, or that you are using an incompatible calendar. 

I’m sorry for the inconvenience! You’d need to either set these up for all events other than Group events, and/or use a compatible calendar if you are not. 

I hope this helps!